Decreased expression of 17β-hydroxysteroid dehydrogenase type 1 is associated with DNA hypermethylation in colorectal cancer located in the proximal colon

<p>Abstract</p> <p>Background</p> <p>The importance of 17β-estradiol (E2) in the prevention of large bowel tumorigenesis has been shown in many epidemiological studies. Extragonadal E2 may form by the aromatase pathway from androstenedione or the sulfatase pathway from estrone (E1) sulfate followed by E1 reduction to E2 by 17-β-hydroxysteroid dehydrogenase (HSD17B1), so <it>HSD17B1 </it>gene expression may play an important role in the production of E2 in peripheral tissue, including the colon.</p> <p>Methods</p> <p><it>HSD17B1 </it>expression was analyzed in colorectal cancer cell lines (HT29, SW707) and primary colonic adenocarcinoma tissues collected from fifty two patients who underwent radical colon surgical resection. Histopathologically unchanged colonic mucosa located at least 10-20 cm away from the cancerous lesions was obtained from the same patients. Expression level of <it>HSD17B1 </it>using quantitative PCR and western blot were evaluated. DNA methylation level in the 5' flanking region of <it>HSD17B1 </it>CpG rich region was assessed using bisulfite DNA sequencing and HRM analysis. The influence of DNA methylation on HSD17B1 expression was further evaluated by ChIP analysis in HT29 and SW707 cell lines. The conversion of estrone (E1) in to E2 was determined by electrochemiluminescence method.</p> <p>Results</p> <p>We found a significant decrease in HSD17B1 transcript (<it>p </it>= 0.0016) and protein (<it>p </it>= 0.0028) levels in colorectal cancer (CRC) from the proximal but not distal colon and rectum. This reduced <it>HSD17B1 </it>expression was associated with significantly increased DNA methylation (<it>p </it>= 0.003) in the CpG rich region located in the 5' flanking sequence of the <it>HSD17B1 </it>gene in CRC in the proximal but not distal colon and rectum. We also showed that 5-dAzaC induced demethylation of the 5' flanking region of <it>HSD17B1</it>, leading to increased occupation of the promoter by Polymerase II, and increased transcript and protein levels in HT29 and SW707 CRC cells, which contributed to the increase in E2 formation.</p> <p>Conclusions</p> <p>Our results showed that reduced <it>HSD17B1 </it>expression can be associated with DNA methylation in the 5' flanking region of <it>HSD17B1 </it>in CRC from the proximal colon.</p

Familial polyposis coli - inducing mutations in APC gene in Poland

Screening for molecular changes within the adenomatous polyposis coli (APC) gene, exons 11-14 and the 5’ half of exon 15, encompassing the mutation cluster region within exon 15, was performed in 30 patients with Familial Polyposis Coli (FAP). All patients were studied by heteroduplex analysis (HA) and single strand conformation polymorphism (SSCP) and molecular changes were found in 7 cases. Protein truncation test (PTT) has been performed in 17 cases in which mutations have not been found earlier, and shortening of protein product was noted in 2 cases. In three cases common deletion of 5 bp at codon 1309 and in one 5 bp deletion at codon 1061 were found. In other cases the molecular changes were demonstrated as heteroduplexes in exon 14 (1 patient), in segments E and F (one patient each) of exon 15, and in two cases the heteroduplexes were within the overlapping sequences of segments E/F and F/G of exon 15, respectively. In families where the molecular changes were found by HA, 7 persons at high risk for FAP were found and advised to undergo regular endoscopic examinations. In three persons at risk the transfer of mutation was excluded

The potential anti‐infective applications of metal oxide nanoparticles: A systematic review

Microbial infections present a major global healthcare challenge, in large part because of the development of microbial resistance to the currently approved antimicrobial drugs. This demands the development of new antimicrobial agents. Metal oxide nanoparticles (MONPs) are a class of materials that have been widely explored for diagnostic and therapeutic purposes. They are reported to have wide‐ranging antimicrobial activities and to be potent against bacteria, viruses, and protozoans. The use of MONPs reduces the possibility of resistance developing because they have multiple mechanisms of action (including via reactive oxygen species generation), simultaneously attacking many sites in the microorganism. However, despite this there are to date no MONPs clinically approved for antimicrobial therapy. This review explores the recent literature in this area, discusses the mechanisms of MONP action against microorganisms, and considers the barriers faced to the use of MONPs in humans. These include biological challenges, of which the potential for an immune response and off‐target toxicity are key. We explore in detail the possible benefits/disbenefits of an immune response being initiated, and consider the effect of production method (chemical vs. green synthesis) on cytotoxicity. There are also a number of technical and manufacturing challenges hindering MONP translation to the clinic which are additionally discussed in depth. In the short term, there are potentially some “quick wins” from the repurposing of already‐approved nanoparticle‐based medicines for anti‐infective applications, but a number of hurdles, both technical and biological, lie in the path to long‐term clinical translation of new MONP‐based formulations. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease Therapeutic Approaches and Drug Discovery > Emerging Technologies Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterial

Patients with Crohn's disease have longer post-operative in-hospital stay than patients with colon cancer but no difference in complications' rate

BACKGROUNDRight hemicolectomy or ileocecal resection are used to treat benign conditions like Crohn's disease (CD) and malignant ones like colon cancer (CC).AIMTo investigate differences in pre- and peri-operative factors and their impact on post-operative outcome in patients with CC and CD.METHODSThis is a sub-group analysis of the European Society of Coloproctology's prospective, multi-centre snapshot audit. Adult patients with CC and CD undergoing right hemicolectomy or ileocecal resection were included. Primary outcome measure was 30-d post-operative complications. Secondary outcome measures were post-operative length of stay (LOS) at and readmission.RESULTSThree hundred and seventy-five patients with CD and 2,515 patients with CC were included. Patients with CD were younger (median = 37 years for CD and 71 years for CC (P &lt; 0.01), had lower American Society of Anesthesiology score (ASA) grade (P &lt; 0.01) and less comorbidity (P &lt; 0.01), but were more likely to be current smokers (P &lt; 0.01). Patients with CD were more frequently operated on by colorectal surgeons (P &lt; 0.01) and frequently underwent ileocecal resection (P &lt; 0.01) with higher rate of de-functioning/primary stoma construction (P &lt; 0.01). Thirty-day post-operative mortality occurred exclusively in the CC group (66/2515, 2.3%). In multivariate analyses, the risk of post-operative complications was similar in the two groups (OR 0.80, 95%CI: 0.54-1.17; P = 0.25). Patients with CD had a significantly longer LOS (Geometric mean 0.87, 95%CI: 0.79-0.95; P &lt; 0.01). There was no difference in re-admission rates. The audit did not collect data on post-operative enhanced recovery protocols that are implemented in the different participating centers.CONCLUSIONPatients with CD were younger, with lower ASA grade, less comorbidity, operated on by experienced surgeons and underwent less radical resection but had a longer LOS than patients with CC although complication's rate was not different between the two groups